Fabrication of integrated circuitry often involves formation of openings within semiconductor material, followed by deposition of one or more materials within the openings.
A problem that can occur during formation of an opening within semiconductor material is that the sidewall peripheries of the opening may comprise a jagged topography. The jagged topography may result from, for example, scalloping of the sidewall peripheries during the etch utilized to form the opening. For instance, a high etch rate of Si may be utilized to increase throughput, and such high etch rate may cause an increased scallop size relative to lower etch rates.
The jagged topography may cause cracking or other defects in materials formed within the opening and along the jagged topography. For instance, scallops are stress concentration points, and may cause failures (cracks and shorts) during subsequent processing, as well as during solder reflow and reliability tests pertaining to some structures. It is therefore desired to develop methods which alleviate jagged topography.
Semiconductor materials may have numerous applications in construction of various integrated circuit structures. In some applications, a semiconductor material may be in the form of the wafer that supports the integrated circuitry. In such applications, openings may be formed to extend into the wafer for fabrication of circuitry, and/or to extend through the wafer for fabrication of through wafer interconnects (TWIs).
In some applications, semiconductor material may be utilized to form pedestals (or spacers) which support an upper structure over a lower structure. For instance, the semiconductor material pedestals may support a macrolens system over an electromagnetic radiation sensor. In some applications, a microlens system may be over the electromagnetic radiation sensor, and the macrolens may be formed to be over the microlens system.
A problem that may occur in forming semiconductor pedestals is that the pedestals may have undesired sharp corners. Accordingly, it would be desired to develop methods of alleviating such sharp corners.